class

class diagram (uml-mcp)

diagram_type: class
Backend: plantuml
Output formats: png, svg, pdf, txt, base64

Shows classes, attributes, methods and relationships between classes

Load the workflow skill uml-mcp-diagrams for URL-first replies, progressive discovery, and which MCP tool to call. This file is notation only; it does not add an MCP tool.

Notation tips

• Visibility: + public, - private, # protected.
• Inheritance: empty triangle; composition filled diamond; aggregation empty diamond; multiplicities on associations.
• Prefer skinparam linetype ortho and left to right direction when the graph is dense.

Themes

Pass theme to generate_uml / generate_uml_image (PlantUML built-in name). The server injects !theme <name> after @startuml when the source has no !theme yet.

Recommended: cerulean, materia, sketchy, cyborg, plain, aws-orange, blueprint, sandstone.

Match the page background (also see MCP prompt diagram_theme):

• light / white: cerulean, materia, plain, sketchy, sandstone
• dark / black: blueprint, cyborg, black-knight, carbon-gray, crt-green
• B&W / print: plain, sketchy, sketchy-outline, mimeograph, lightgray

Or embed in source:

@startuml
!theme cerulean
' … diagram …
@enduml

Starter template

@startuml
class Car {
  - brand: string
  - speed: int
  + drive(): void
}
class Engine {
  - horsepower: int
  + start(): void
}
Car --> Engine
@enduml

Example

@startuml
class Account {
  - balance: decimal
  - accountNumber: string
  + deposit(amount: decimal): void
  + withdraw(amount: decimal): boolean
}
class Customer {
  - name: string
  - id: string
  + getAccounts(): List<Account>
}
class Transaction {
  - amount: decimal
  - date: DateTime
}
Customer "1" --> "*" Account : owns
Account "1" --> "*" Transaction : contains
@enduml

Render with uml-mcp